Buggy code:
public List < ColumnOrSuperColumn > thriftifyColumns ( Collection < IColumn > columns , boolean reverseOrder ) { } private List < ColumnOrSuperColumn > thriftifySuperColumns ( Collection < IColumn > columns , boolean reverseOrder ) { } private static Clock thriftifyIClock ( IClock clock ) { } private Map < byte [ ] , List < ColumnOrSuperColumn > > getSlice ( List < ReadCommand > commands , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } private List < ColumnOrSuperColumn > thriftifyColumnFamily ( ColumnFamily cf , boolean subcolumnsOnly , boolean reverseOrder ) { } public List < ColumnOrSuperColumn > get_slice ( byte [ ] key , ColumnParent column_parent , SlicePredicate predicate , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } public Map < byte [ ] , List < ColumnOrSuperColumn > > multiget_slice ( List < byte [ ] > keys , ColumnParent column_parent , SlicePredicate predicate , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } private Map < byte [ ] , List < ColumnOrSuperColumn > > multigetSliceInternal ( String keyspace , List < byte [ ] > keys , ColumnParent column_parent , SlicePredicate predicate , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } public ColumnOrSuperColumn get ( byte [ ] key , ColumnPath column_path , ConsistencyLevel consistency_level ) throws InvalidRequestException , NotFoundException , TimedOutException , UnavailableException { } public int get_count ( byte [ ] key , ColumnParent column_parent , SlicePredicate predicate , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } public Map < byte [ ] , Integer > multiget_count ( String table , List < byte [ ] > keys , ColumnParent column_parent , SlicePredicate predicate , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } public void insert ( byte [ ] key , ColumnParent column_parent , Column column , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } public void batch_mutate ( Map < byte [ ] , Map < String , List < Mutation > > > mutation_map , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } public void remove ( byte [ ] key , ColumnPath column_path , Clock clock , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException { } private void doInsert ( ConsistencyLevel consistency_level , List < RowMutation > mutations ) throws TimedOutException , UnavailableException { } public KsDef describe_keyspace ( String table ) throws NotFoundException { } public List < KeySlice > get_range_slices ( ColumnParent column_parent , SlicePredicate predicate , KeyRange range , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException , TException { } private List < KeySlice > thriftifyKeySlices ( List < Row > rows , ColumnParent column_parent , SlicePredicate predicate ) { } public List < KeySlice > get_indexed_slices ( ColumnParent column_parent , IndexClause index_clause , SlicePredicate column_predicate , ConsistencyLevel consistency_level ) throws InvalidRequestException , TimedOutException , UnavailableException , TException { } public List < KsDef > describe_keyspaces ( ) throws TException { } public String describe_cluster_name ( ) throws TException { } public String describe_version ( ) throws TException { } public List < TokenRange > describe_ring ( String keyspace ) throws InvalidRequestException { } public String describe_partitioner ( ) throws TException { } public List < String > describe_splits ( String keyspace , String cfName , String start_token , String end_token , int keys_per_split ) throws TException { } public AccessLevel login ( AuthenticationRequest auth_request ) throws AuthenticationException , AuthorizationException , TException { } public void logout ( ) { } protected void checkKeyspaceAndLoginAuthorized ( AccessLevel level ) throws InvalidRequestException { } private void schedule ( ) { } private void release ( ) { } private static void applyMigrationOnStage ( final Migration m ) throws InvalidRequestException { } public String system_add_column_family ( CfDef cf_def ) throws InvalidRequestException , TException { } public String system_drop_column_family ( String column_family ) throws InvalidRequestException , TException { } public String system_rename_column_family ( String old_name , String new_name ) throws InvalidRequestException , TException { } public String system_add_keyspace ( KsDef ks_def ) throws InvalidRequestException , TException { } public String system_drop_keyspace ( String keyspace ) throws InvalidRequestException , TException { } public String system_rename_keyspace ( String old_name , String new_name ) throws InvalidRequestException , TException { } private CFMetaData convertToCFMetaData ( CfDef cf_def ) throws ConfigurationException , InvalidRequestException { ColumnFamilyType cfType = ColumnFamilyType . create ( cf_def . column_type ) ; if ( cfType == null ) { throw new InvalidRequestException ( ( "Invalid<seq2seq4repair_space>column<seq2seq4repair_space>type<seq2seq4repair_space>" + ( cf_def . column_type ) ) ) ; } ClockType clockType = ClockType . create ( cf_def . clock_type ) ; if ( clockType == null ) { throw new InvalidRequestException ( ( "Invalid<seq2seq4repair_space>clock<seq2seq4repair_space>type<seq2seq4repair_space>" + ( cf_def . clock_type ) ) ) ; } AbstractReconciler reconciler = DatabaseDescriptor . getReconciler ( cf_def . reconciler ) ; if ( reconciler == null ) { if ( clockType == ( ClockType . Timestamp ) ) <START_BUG> reconciler = new TimestampReconciler ( ) ; <END_BUG> else throw new ConfigurationException ( ( "No<seq2seq4repair_space>reconciler<seq2seq4repair_space>specified<seq2seq4repair_space>for<seq2seq4repair_space>column<seq2seq4repair_space>family<seq2seq4repair_space>" + ( cf_def . name ) ) ) ; } return new CFMetaData ( cf_def . keyspace , cf_def . name , cfType , clockType , DatabaseDescriptor . getComparator ( cf_def . comparator_type ) , ( ( cf_def . subcomparator_type . length ( ) ) == 0 ? null : DatabaseDescriptor . getComparator ( cf_def . subcomparator_type ) ) , reconciler , cf_def . comment , cf_def . row_cache_size , cf_def . preload_row_cache , cf_def . key_cache_size , cf_def . read_repair_chance , ( cf_def . isSetGc_grace_seconds ( ) ? cf_def . gc_grace_seconds : CFMetaData . DEFAULT_GC_GRACE_SECONDS ) , ColumnDefinition . fromColumnDef ( cf_def . column_metadata ) ) ; } public void truncate ( String cfname ) throws InvalidRequestException , UnavailableException , TException { } public void set_keyspace ( String keyspace ) throws InvalidRequestException , TException { } public Map < String , List < String > > check_schema_agreement ( ) throws InvalidRequestException , TException { } }

Fix:
reconciler = TimestampReconciler . instance ;